Details

Autor(en) / Beteiligte

• Zhang, Lianke
• Guo, Jinyue
• Huang, Xuemin
• Wang, Weida
• Sun, Peng
• Li, Yumei
• Han, Jianhong

Titel

Functionalized biochar-supported magnetic MnFe2O4 nanocomposite for the removal of Pb(ii) and Cd(ii)

Ist Teil von

• RSC advances, 2019-01, Vol.9 (1), p.365-376

Ort / Verlag

Cambridge: Royal Society of Chemistry

Erscheinungsjahr

2019

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• In this study, a novel magnetic biochar-MnFe 2 O 4 nanocomposite (BC/FM) was prepared using low-cost corn straw and MnFe 2 O 4 by sol-gel/pyrolyzing route using egg white, which has abundant functional groups (-NH 2 and -COOH). Following that, its composition, morphology and structure was characterized by various techniques including SEM-EDX, BET, XRD, and VSM. Batch experiment of the adsorption for Pb( ii ) and Cd( ii ) including influence of pH, kinetics, isotherm and thermodynamics was also studied. The results demonstrated that biochar could effectively support MnFe 2 O 4 , which displayed high dispersion on the surface of the biochar and possessed abundant functional groups and high surface area contributing to superior performance on Pb( ii ) and Cd( ii ) removal. Therein, MnFe 2 O 4 with high magnetism is convenient for separating the magnetic BC/FM from an aqueous medium. Adsorption experiment results indicate that Pb( ii ) and Cd( ii ) removal by BC/FM was closely related to pH with the best value of pH 5.0, and the process reached equilibrium in 2 h. The adsorption process is well-described by the pseudo-second-order kinetic model and Sips (Freundlich-Langmuir) model. Thermodynamic studies suggest that the adsorption process is spontaneous and exothermic. The maximum experimental adsorption capacity of BC/FM is 154.94 and 127.83 mg g −1 for Pb( ii ) and Cd( ii ), respectively, in single-solute system, which is higher than that of some of the other adsorbents of biochar or biochar-based composites. In bi-solute system, the preferential adsorption order of BC/FM for the two metals is Pb( ii ) prior to Cd( ii ). Finally, FTIR and XPS analysis verified that the main mechanism of Pb( ii ) and Cd( ii ) removal by BC/FM is by forming Pb/Cd-O or complexation of carboxyl and hydroxyl and ion exchange. Therefore, the prepared magnetic BC/FM composite, as an excellent adsorbent, exhibited potential applications for the removal of Pb( ii ) and Cd( ii ) from wastewater. In this study, a novel magnetic biochar-MnFe 2 O 4 nanocomposite (BC/FM) was prepared using low-cost corn straw and MnFe 2 O 4 by sol-gel/pyrolyzing route using egg white, which has abundant functional groups (-NH 2 and -COOH).